Stained Granite tiles problem

Dear Sirs,
Have nice day! We have checked your picture. Really they are problem
granite tile. I think it is due to granite quality. It is possible that
your supplier use chemical liquid to brush on the granite surface. They
want to get rid of Yellow Dot (Fe) on the granite. After using chemical
liquid, the granite tile will be very white and cleaning, but after
installing, the problem will be shown. It is your picture's showing. I
would like to suggest you use granite cleaning liquid at first, and then
using granite protecting liquid after cleaning. It will reduce the terrible
yellow area.
If you have other question, and if I can, I would like to support you
again. We are one of Chinese granite manufactory. Maybe we have some
experience on this line.
Now it is Chinese New Year, wish Happy New Year!
Best Regards.
Catherine